Components formed from thermoplastic are frequently joined by spin welding or friction welding in which the interfaces of the two components are brought together under pressure. While one component is held stationary the other component is rotated against the stationary part at a high rate of speed creating frictional heat causing the thermoplastic at the interfaces to melt and fuse together. A strong, hermetic seal results from the spin weld.
It is common for the modern intake manifold for an internal combustion engine to utilize spin welded caps and spigots. A spin-welded cap may be effectively employed in a variety of manifold applications, such as for a sealing arrangement for an internal bracing or post arrangement in an intake manifold having two halves held together by a fastener. To provide a fluid-tight seal, a spin welded cap may be provided over the head of the fastener.
Spin welding is often useful where the caps and spigots sometimes cannot be directly molded into the part due to restrictions related to tooling or part interchangeability. However, spin welding, while providing a desirable seal and a strong bond, has space and structure limitations. It is relatively expensive to undertake from both labor and tooling perspectives.
Thus the use of spin welded caps and spigots, while providing an attractive alternative to other methods of fastening and sealing, represents an expensive and tooling- and cycle time-intensive approach. Accordingly, a system for providing a cap that also serves a sealing function for use with the intake manifold of a vehicle that is easy to install, requires minimal tooling, and provides an effective seal remains wanting.